Should I teach my daughter a lesson the "old fashioned way?"?

I'm a mother and my sopre daughter is behaving completely inappropriately. Her grades are dropping, a month and a half ago she got suspended because she was cheering while 2 girls were fighting in the cafeteria, last week I caught her trying to sneak out of the house at night to go to a party with alcohol, drugs, and , and now I just received a bunch of emails presumably from anonymous (at least to me) people informing me (and posting the link) to sites on which my daughter had posted pictures and videos in which she was showing the world her underwear! My patience is up! I know she's not depressed or anything because she's all about partying! I know I'm going to ground her for a month but I want to her too! Do you think she deserves that? She's 15, I think she does! But I want to know what you think!